The best performance of both FV and SR was at the agricultural field, where the measurements are well in the surface layer while the worst in the case of the tall forest where the measurements are still in the roughness sublayer and the roughness layer depth (with its inherent uncertainty) needs to be taken into account in the calculations. After the selection of the most reliable approaches, regression analyses against EC shows that both methods can estimate sensible heat flux with slopes within ☑0 % from unity and R2 >0.9 across all the three sites. However, it can be put in a more universal framework where the parameters of both methods requiring calibration are represented by joint physically based parameters such as surface aerodynamic properties rather than similarity constants in the case of FV or the mean volume over the area of the air parcels in the case of SR. We show that the frequently reported need for the calibration (e.g. This presentation provides an overview of the FV and SR approaches, including new perspectives as well as identifies the common framework of the methods rather than carrying out their mere comparison. 10 Hz) air temperature variation while some approaches require additional wind velocity measurements. In principle, both methods require the monitoring of high frequency (e.g. Until now, the differences between the methods have not been fully standardized or clarified. Since the introduction of FV and SR, several versions of these methods have been proposed, with significantly differing perspectives and assumptions. By considering the position of the sensors with respect to canopy, the measurements at these three sites were carried out in the atmospheric surface layer, roughness layer, and roughness to surface transitional layer, respectively. Here, two alternative methods, flux-variance (FV) and surface renewal (SR), are evaluated in quantifying sensible heat flux at three sites representing agricultural (wheat field, straw and bare soil), agroforestry (pine-switchgrass intercroping) and natural forested wetland (mixed conifer-deciduous wetland forest) systems that span a broad range of canopy height and structural complexity. However, the cost and complexity of EC often limit its widespread deployment, and therefore, alternatives need to be considered. The annual variation of net radiation shows a typical pattern of Q* being at a maximum during the summer and minimum during the winter.Eddy covariance (EC) has become the standard method for determining energy fluxes at the soil-plant-atmosphere interface. West Palm Beach, Florida is located in the warm and moist tropical wet and dry (savanna) climate.
\): West Palm Beach, Fl energy balance (ly/day)
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